Clean, but not green: Emission assessment, forecast modelling and policy solutions for plastic microbeads from personal care products in India

Intentionally added plastic microbeads in personal care products (PCP) are an underestimated source of microplastics. These microbeads are added as fillers, to increase product volume or aesthetics and allegedly have the purpose of cleansing and exfoliation. To assess and forecast microbead emissions in India, this study analysed 45 items from four different categories of personal care products: face wash, face scrub, shower gel and body scrub available in the Indian market and determined microbead abundance, size, colour, shape and polymer composition. Also, an emission estimation and time-series-based forecast for 2030 was done using ARIMA (0,2,0) for individual categories and overall. The results indicate that 45.00 % of the products contained irregular or smooth microplastics, with Polyethylene being the dominant polymer, followed by Polypropylene, Polystyrene, Polyurethane and Polycaprolactone. A significant number of products (23.33%) contained cellulose microbeads, with ambiguity regarding their biodegradability. The identified microbeads were mainly irregular in shape and granular in texture, especially scrubs. White/transparent colour dominated the identified microbeads, followed by blue, pink, yellow, red and green. Approximately 1.34% of the total product contained plastic microbeads, with 5.04% and 0.04% being the highest and lowest percentages quantified. The average size of microbeads was found to be 640.74 μm, 452.45 μm, 556.66 μm and 606.30 μm in different categories. The overall annual emission estimation was 3.51 × 1019(highest), 2.14 × 1018(lowest) and 1.37 × 1019(average) in 2021 and forecasted to be 4.12 × 1019(highest), 2.52 × 1018(lowest) and 1.61 × 1019(average)in 2030. This exorbitantly high value is due to India's significant population, globalisation, inefficient wastewater efficiency, growing economy and disposable income. A lack of policies and adequate regulations further add to this. This study emphasises and recommends the development of stringent policies and other well-tailored mitigation measures for intentionally added microbeads in PCP in India. The study recommends some policy measures to curb this threat.